Atrazine affects fish reproduction
Atrazine, one of the most commonly used herbicides in the world, has been shown to affect reproduction of fish, according to a new U.S. Geological Survey (USGS) study. “Concentrations of atrazine commonly found in agricultural streams and rivers caused reduced reproduction and spawning, as well as tissue abnormalities in laboratory studies with fish,” said USGS scientist Donald Tillitt, the lead author of the study published in Aquatic Toxicology.
Fathead minnows were exposed to atrazine at the USGS Columbia Environmental Research Center in Columbia, Missouri, and observed for effects on egg production, tissue abnormalities, and hormone levels. Substantial reproductive effects were observed at concentrations below the EPA water-quality guideline.
Study results show that normal reproductive cycling was disrupted by atrazine and fish did not spawn as much or as well when exposed to atrazine. Researchers found that total egg production was lower in all atrazine-exposed fish, as compared to the non-exposed fish, within 17 to 20 days of exposure. In addition, atrazine-exposed fish spawned less, and there were abnormalities in reproductive tissues of both males and females.
Atrazine is one of the most commonly-used herbicides in the world and is used on most corn, sugarcane, and sorghum acreage in the United States. It is used to stop pre- and post-emergence broadleaf and grassy weeds, and is generally applied in the spring when most fish in North America are attempting to reproduce.